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| author | Peter Zijlstra <peterz@infradead.org> | 2013-11-19 16:41:49 +0100 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2014-03-12 13:25:38 +0100 |
| commit | a2198407845fa9d85b590eafafacf3b6a82d3528 (patch) | |
| tree | dfd2e8780f9448a4496541c0ffc1a638502de8ba /kernel | |
| parent | ec6317cc7e5e333acdfa2426c96d372bfc920077 (diff) | |
| download | lwn-a2198407845fa9d85b590eafafacf3b6a82d3528.tar.gz lwn-a2198407845fa9d85b590eafafacf3b6a82d3528.zip | |
sched: Avoid NULL dereference on sd_busy
commit 42eb088ed246a5a817bb45a8b32fe234cf1c0f8b upstream.
Commit 37dc6b50cee9 ("sched: Remove unnecessary iteration over sched
domains to update nr_busy_cpus") forgot to clear 'sd_busy' under some
conditions leading to a possible NULL deref in set_cpu_sd_state_idle().
Reported-by: Anton Blanchard <anton@samba.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131118113701.GF3866@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/core.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 6135b7c6bcfe..bc2f26d03751 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5132,8 +5132,9 @@ static void update_top_cache_domain(int cpu) if (sd) { id = cpumask_first(sched_domain_span(sd)); size = cpumask_weight(sched_domain_span(sd)); - rcu_assign_pointer(per_cpu(sd_busy, cpu), sd->parent); + sd = sd->parent; /* sd_busy */ } + rcu_assign_pointer(per_cpu(sd_busy, cpu), sd); rcu_assign_pointer(per_cpu(sd_llc, cpu), sd); per_cpu(sd_llc_size, cpu) = size; |